nasa_epic_earth

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden. It discloses that the endpoint is keyless and that the output includes URLs and geometry, which is useful. However, it does not mention rate limits, error behavior, or explicitly state that it is a read-only operation beyond the word 'Get'. Some behavioral context is added but significant gaps remain.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with the primary purpose, and no filler. Every word contributes to understanding the tool's function and output. Excellent conciseness and structure.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool has 3 optional parameters, no annotations, and no output schema, the description provides a high-level overview but lacks details on response structure, collection option meanings, and error handling. It adequately covers the main function but is not fully complete for an agent to invoke without additional inference.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is only 33% (only 'date' has a description). The description adds no parameter information whatsoever, failing to explain the 'collection' enum values or 'limit' semantics. Since coverage is low, the description needed to compensate but did not, leaving the agent to infer parameter meanings from names and enum values alone.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses a specific verb ('Get') and resource ('DSCOVR/EPIC full-disc Earth images') and explicitly mentions direct PNG/JPG/thumbnail URLs and spacecraft geometry, which clearly distinguishes it from sibling tools like nasa_apod or nasa_search_media that serve different content.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies usage for EPIC imagery but does not explicitly state when to prefer this tool over alternatives or provide exclusion criteria. It lacks comparison to sibling tools or guidance on when not to use this tool, though the specificity of the content gives some context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.